Itchy Red Spot on Bottom of Foot

Carly • Scorpio ♏️ Happily married 8/19/18 💍 Baby #1 8/17/19, Baby #2 due 11/7/21
For the past few days, the bottom of my foot has been itching pretty badly. Today, she. I took my sock off, I noticed this small red bump. This is definitely the source of the itching, but what could it be? My first thought was a spider bite, but it seems to be blister-like with a small amount of fluid. Help!?